The control and flow of surface water such as rain water is important in preventing the buildup of surface water adjacent foundations of other structures. Generally, drywells are employed to store large quantities of surface water therein and to discharge the surface water beneath the ground away from the foundation wall or structure and over a defined distribution area. Typically, drywells are composed of heavy, precast concrete structures, generally cylindrical in shape, but may also be square or rectangular, with one or more side wall holes of large diameter for inlet and outlet pipe. A plurality of generally smaller diameter holes, are usually uniformly distributed over a substantial part of the side walls and, precast in the cylindrical concrete wall, permit the drainage of water radially outward from the drywell. Typically, the drywell includes a heavy, solid, concrete bottom and top cover, such as a removable bottom and top cover. Generally, the top cover may have an opening therein in the top surface to serve as an opening with or without a grate for receiving surface water or the bottom cover may have an opening therein for the discharge of water.
The parent application is directed to a composite drywell and drywell system and method for employing a composite drywell, which composite drywell has a removable top and bottom section. The drywell is composed of a plurality of separate edge interlocked arcuate wall sections, which together form the peripheral wall of the drywell. Each section having a one side edge with an opening extending substantially the length of the side edge and the other side edge having a beaded side edge, or other means, for interlocking the side edges of related sections together, typically to form a cylindrical drywell wall. The sections have a plurality of large and small diameter, or other, ports for the introduction and distribution of water from the drywell. The composite drywell comprises an injection-molded plastic or polymeric drywell, which is lightweight and, with the arcuate sections, may be easily stored together in a nesting-type arrangement for easy transport. Such composite drywell may include removable top and bottom sections which may be fitted to the top and bottom of the drywell.
It is desirable to provide for a drywell cover and drywell with said cover, which drywell cover may be easily and inexpensively molded of a plastic type material, particularly as a single, injected molded piece and which cover is designed to have sufficient strength as to be employed as a top or bottom cover for a drywell, particularly a composite drywell described in the parent application. The drywell cover may be easily transported to the desired site, together with the sections of the composite drywell, and installed on site. The drywell cover has many advantages over the heavy pre-cast concrete covers typically employed with drywell.